000174663 001__ 174663
000174663 005__ 20181117104053.0
000174663 0247_ $$2doi$$a10.5075/epfl-thesis-5293
000174663 02470 $$2urn$$aurn:nbn:ch:bel-epfl-thesis5293-7
000174663 02471 $$2nebis$$a6791841
000174663 037__ $$aTHESIS_LIB
000174663 041__ $$aeng
000174663 088__ $$a5293
000174663 245__ $$aMiniature Mobile Systems for Inspection of Ferromagnetic Structures
000174663 269__ $$a2012
000174663 260__ $$aLausanne$$bEPFL$$c2012
000174663 300__ $$a165
000174663 336__ $$aTheses
000174663 520__ $$aPower plants require periodical inspections to control       their state. To ensure a safe operation, parts that could       fail before the next inspection are repaired or replaced,       since a forced outage due to a failure can cost up to       millions of dollars per day. Non-Destructive Testing (NDT)       methods are used to detect different defects that could       occur, such as cracks, thinning, corrosion or pitting. Some       parts are inspected directly in situ, but may be difficult to       access; these can require opening access holes or building       scaffoldings. Other parts are disassembled and inspected in       workshops, when the required inspection tools cannot be       moved. In this thesis, we developed innovative miniature mobile       systems able to move within these small and complex       installations and inspect them. Bringing sensors to       difficult-to-access places using climbing robots can reduce       the inspection time and costs, because some dismantling or       scaffolding can be eliminated. New miniature sensors can help       to inspect complex parts without disassembling them, and       reduce the inspection costs, as well. To perform such inspections, miniature mobile systems       require a high mobility and keen sensing capabilities. The       following approach was used to develop these systems. First,       different innovative climbing robots are developed. They use       magnetic adhesion, as most structures are made of       ferromagnetic steel. Then, vision is embedded in some of the       robots. Performing visual inspections becomes thus possible,       as well as controlling the robots remotely, without viewing       them. Finally, non-visual NDT sensors are developed and       embedded in some of the robots, allowing them to detect       defects that simple vision cannot detect. Achieving the       miniaturization of the developed systems requires strong       system integration during these three steps. A set of       examples for the different steps has been designed,       implemented and tested to illustrate this approach. The Tripillars robots, for instance, use caterpillars, and       are able to climb on surfaces of any inclination and to pass       inner angles. The Cy-mag3Ds robots use an       innovative magnetic wheel concept, and are able to climb on       surfaces of any inclination and to pass inner angles, outer       angles and surface flips. The Tubulos robots move in tubes of       25 mm diameter at any inclination. All robots embed the       required electronics, actuators, sensors and energy to be       controlled remotely by the user. Wireless transmission of the       commands signals allows the systems to maintain their full       mobility without disturbing cables. Integrating Hall sensors       near the magnetic systems allows them to measure the adhesion       force. This information improves the security of the robots,       since when the adhesion force becomes low, the robots can be       stopped before they fall. The Tubulo II uses Magnetic       Switchable Devices (MSDs) for adhesion. An MSD is composed of       a ferromagnetic stator and one or more moving magnets; it has       the advantage of requiring only a low force to switch on or       off a high adhesion force. MSDs have the advantage of being       easy to clean of the magnetic dust that is present in most       real environments and that sticks strongly to magnetic       systems. As an additional step toward inspection, a camera is       embedded on the Cy-mag3D II and the Tubulos. It       allows these robots to inspect visually the structures the       robots move in, and to control them remotely. The perspective       of a climbing robot in an unknown environment is often not       enough to give the user a sense of its scale, and to move       efficiently in it. A distance sensor is designed and embedded       on the Cy-mag3D II, which increases the user's       perception of the environment substantially; Finally, an innovative miniature Magnetic Particle       Inspection (MPI) system was developed to inspect turbine       blades without disassembling them. An MSD is used to perform       the required magnetization. The system can automatically       inspect a flat surface, performing all the required steps of       MPI: magnetize, spray magnetic particles, record images under       UV light and demagnetize. Thanks to the strong integration       and miniaturization, the system can potentially inspect       complex parts such as steam turbines.
000174663 6531_ $$aInspection robot
000174663 6531_ $$aClimbing robot
000174663 6531_ $$aMobile robot
000174663 6531_ $$aMagnetic adhesion
000174663 6531_ $$aVision
000174663 6531_ $$aNon-Destructive Testing
000174663 6531_ $$aIntegration
000174663 6531_ $$aRobot d'inspection
000174663 6531_ $$aRobot grimpant
000174663 6531_ $$aAdhésion magnétique
000174663 6531_ $$aVision
000174663 6531_ $$aIntégration
000174663 6531_ $$aContrôle Non Destructif
000174663 700__ $$0242147$$aSchoeneich, Patrick$$g155115
000174663 720_2 $$0240589$$aMondada, Francesco$$edir.$$g102717
000174663 8564_ $$s50152878$$uhttps://infoscience.epfl.ch/record/174663/files/EPFL_TH5293.pdf$$yTexte intégral / Full text$$zTexte intégral / Full text
000174663 909C0 $$0252016$$pLSRO
000174663 909CO $$ooai:infoscience.tind.io:174663$$pSTI$$pthesis$$pthesis-bn2018$$pDOI$$qDOI2$$qGLOBAL_SET
000174663 918__ $$aSTI$$cIMT$$dEDPR
000174663 919__ $$aLSRO1
000174663 920__ $$b2012
000174663 970__ $$a5293/THESES
000174663 973__ $$aEPFL$$sPUBLISHED
000174663 980__ $$aTHESIS